WILL THE ANIMALS AT THE BOT TOM OF THE FOOD CHAIN SOME DAY BECOME EXTINCT?

Biological systems are difficult to predict, but even species low down the food chain can get into difficulties when the system is unbalanced. Take Australia, for example; in the 1950s the number of rabbits exploded. In similar circumstances, this boom can easily be followed by a bust through an animal population eating all its own food supply.

Also in Australia, cattle introduction led to such a buildup of cowpats that they were destroying the habitat through the buildup of their own waste – at least until a suitable dung beetle was introduced. Generally speaking, predator species help provide balance, keeping animals lower down the food chain in check, therefore allowing plants to provide the resources on which the rest of the system depends. Meanwhile, other contributors to the system, such as decomposers, also help the system stay in shape.